This is aquarium fish tank oxygen air pump hydroponics + 2 air stone + 2M silicone tube, with functions of multi-level , low noise, -free compressed air pure. And with regulating valves, it can effectively regulate the air displacement. It is high-performance, large volume, for small and medium-sized fish tank plus oxygen. It is perfectly suitable for using in all kinds of high-grade aquarium, aquaculture oxygenation, spout decoration, etc. Features - ColorBlack - Package weight: 11.5 oz/327g. - The length of the tube: 100cm, 115cm. -Note: Chinese flat plug compatible with US outlets How to use 1. The voltage and the frequency of the air feed pump using must be meet requirements. 2. The position of placing the air pump must be higher than that of the aquarium, which can avoid the water flowing into the inside place of the machine following the 3. Connect the gas piping to the air outlet of the air pump, the uniformly distribute the vesicle stone in the aquarium, on power supply and the air pump will be air-entrapping and oxygenation 4. You can choose single air outlet or outlet on the oxygen demand to reach the air supply and oxygenation 5. The filtration cotton of the air pump and the vesicle stone must be washed and replaced in every three months 6. The air pump should disconnect with the power supply, and placed in the dry environment when do not used Package list: 1 * 3W aquarium air pump 2 * air stone 2 * silicone tube